Analyse the given data and answer the questions given below:
Three pendulums have the same length but different bob masses.
| Pendulum | Length | Bob Mass |
| \(A\) | \(100\ cm\) | \(20\ g\) |
| \(B\) | \(100\ cm\) | \(40\ g\) |
| \(C\) | \(100\ cm\) | \(60\ g\) |
Use this information to answer the following descriptive questions.
1. Three pendulums \(A\), \(B\) and \(C\) have the same length of \(100\ cm\), but their bob masses are \(20\ g\), \(40\ g\) and \(60\ g\), respectively.
Identify the variable that is changed and the variable that is kept constant. Explain why this arrangement is useful for investigating the effect of mass on the time period of a pendulum.
The is the variable that is changed.
The is kept constant for all three pendulums.
Keeping the length constant is important because the investigation aims to study the . If both mass and length were changed at the same time, it would be difficult to determine which factor caused any observed change in the time period.
2. The three pendulums have identical lengths but different masses. What would you expect about their time periods? Explain your answer using the experimental conditions given in the table.
The three pendulums are expected to have , provided that the other experimental conditions are kept the same.
Although their bob masses are different—\(20\ g\), \(40\ g\) and \(60\ g\)—all three pendulums have the .
The of a simple pendulum. Therefore, changing the mass while keeping the length constant should not produce a significant change in the time period.
Thus, Pendulums \(A\), \(B\) and \(C\) should be expected to have .
3. Suppose the students perform the experiment and obtain nearly the same time period for all three pendulums. What conclusion can be drawn from this observation? Why is this conclusion important when investigating the factors affecting the time period of a simple pendulum?
If all three pendulums have , we can conclude that the mass of the bob the time period of a simple pendulum, when the length and other relevant conditions are kept the same.
This observation is important because it helps us identify which factors do and do not affect the . Since the length was kept constant and only the mass was changed, the experiment provides evidence that changing the bob's mass does not produce a significant change in the time period.